Numerous applications find it useful to control characteristics of output waveforms provided by various types of circuits, especially applications where extreme accuracy and long-term stability is desired or necessary. Critical circuit function in such applications is greatly impacted by variations in component performance. For example, the performance characteristics of amplifiers may vary due to errors resulting from drift of offset and gain. Such errors may restrict the frequency range, impair the accuracy and stability, and slow the response time of circuitry.
One previously known approach of compensating for errors caused by drift centers upon controlling the entire collection of components in a circuit. This method typically employs circuit designs that use components with exceptional qualities. Unfortunately, an undesirable consequence of this method is increased cost, as components of exceptional quality are generally expensive. An additional consequence of this method is that it relies on careful selection of all components to regulate overall performance of the circuit. As a circuit becomes more complex, the number of components increases, which results in a greater chance of error. While this approach of controlling circuit component selection can compensate for error, it does so without minimizing expense and risk exposure inherent in circuits with many components.